Fan



FIG. 1 is a perspective view of a fan showing the claimed invention;

FIG. 2 is a side view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a top plan view thereof.

The broken lines illustrate portions of the fan which form no part of the claimed design. 

The ornamental design for a fan, as shown and described. 